A passive optical network (PON) is a network that uses unpowered optical splitters to enable a single optical fiber to serve multiple premises. A PON typically includes an optical line terminal (OLT) at one end of the network, and multiple optical network units (ONUs) near the end users of the network. Optical signals are transmitted from the OLT via an optical fiber of the network, and transmitted to each of multiple premises via one or more unpowered optical splitters. Use of the unpowered optical splitters attenuates the optical signals such that the signal strength decreases relative to noise and interference over the optical fiber(s) of the network.
Other types of fiber optic networks use one or more Optical Add/Drop Multiplexers (OADMs), instead of optical splitters, for transmitting data at high speeds to and from customer locations. Such networks typically include central offices that each include the one or more OADMs, such as Reconfigurable OADMs (ROADMs), that perform optical wavelength selective switching of optical signals on incoming optical fibers to outgoing optical fibers such that data traffic may be routed to and from customer locations. Each customer location may include its own ROADM for selective switching of optical signals received from the ROADM in the central office. The ROADM in each customer location switches incoming optical signals to destination customer site equipment, or switches outgoing optical signals from source customer site equipment to the ROADM in the central office.